In-between centers and suburbs? Increasing differentials in recent demographic dynamics of Italian metropolitan cities

Verifying the intrinsic stability of demographic processes over time and space is a pivotal task from both science and policy perspectives. Compared with other regions of the old continent, a latent peculiarity of demographic systems in Southern Europe is their persistent heterogeneity over space, especially observed across metropolitan regions. 'Centers' and 'peripheries' are thus becoming representative of, respectively, territories undergoing demographic growth and decline. The former corresponds to urban areas, being attractive for different population segments. The present study illustrates the results of a statistical analysis of total population data over time (2011-2020) and its decomposition in natural increase and net migration rates in 14 metropolitan cities of Italy. Assuming that central and peripheral (e.g., suburbs) locations show differential trends of natural increase and net migration, our analysis verifies whether (i) central locations behave homogeneously in terms of population dynamics, and whether (ii) a North-South gradient holds. Results indicate how (metropolitan) demographic patterns no longer reflect a traditional gap between Northern and Southern regions, while outlining a subtler divide in growing and declining contexts. The few still-growing metropolitan areas were all located in North-Central Italy, and reflect more polarized socioeconomic contexts than in the past. Internal migration was likely the most powerful factor that discriminates growing from declining cities. Such evidence indicates that strengthening the self-restraining capacity of Southern Italian territories contributes to increase their attractiveness of international migration flows, counteracting demographic shrinkage.